Adjustment of electric lamps



C. 0. HARRINGTON. ADJUSTMENT 0F ELECTRIC LAMPS.

APPL'ICATION FILED APR. 7. I916.

Patented Feb. 10,1920.

INVINTOR.

, locating a filament in the bulb in a given UNITED STATES PATENT OFFICE.

CLINTON O. HARRINGTON, OF EDGEWOOD BOROUGH, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A COR- PORATION OF IBENNSYLVANIA.

Specification of Letters Patent.

Patented Feb. 10, 1920.

Application filed April 7, 1916. Serial No. 89,636.

incandescent electric lamps.

In light signals comprising a lam and means (such as a lens or a reflector or 0th) for projecting a beam of light from the lamp, it is usual to employ concentrated filament lamps for reasons of efliciency.

This filament, which is usually in the shape of a spiral, must be located at a definite point with respect to the projecting means, this point usually being the focus.

One object of my invention is the provision of means for adjusting the location .of the filament of each lamp with respectto the lamp base or other member of the lamp by which it is located in the light signal, so

that the filament of the lamp occupies a definite. position relative to said base or other locating member. Consequently, when such a lamp is secured in the light signal, its filament occupies a definite position with respect to the projecting means of the light signal. By using correct proportions, this position of the filament may be made the focal point. It is apparent that any lamp correctly adjusted according to my invention, may be used in any signal of the same dimensions, without the necessity of adjusting the position of the lamp to bring the filament into the focus.

I will describe one form of apparatus, and one method of using the same, both embodying my invention, and with them point out the novel features thereof in claims.

In the accompanying drawings, Figure 1 is a view showing, partly in elevation and partly in section, one form of apparatus for supporting the bulb of an incandescent lamp. Fig. 2 is a view showing means for position with relation to part of the apparatus shown in Fig. 1. Fig. 3 is a" view showing means for attaching a base to the bulb in a given position with respect to the filament- Similar reference characters refer to similar parts in each of the several views.

Referring first to Fig. 1, the reference character designates a base plate on which are mounted two vertical standards 51. Means are provided on this base for securing a lamp bulb to the base; as here shown, these means comprise springs 52 of the shape shown in the drawing mounted on plate 50'by screws 52% These springs are disposed equidistant from a vertical axis a-b, which is preferably midway between standards 51. Although but two springs appear on the drawing, it is understood that several others are mounted on plate '50 in similar manner, so that when a lamp bulb 53- is inserted between them, they hold the- 51 until its shoulder 58 rests on the bulb surface. 'It is easily seen that the lamp bulb is now-held in a position wherein its vertical axis substantially coincides with axis w-b. Furthermore, member 56 is located in a definite position with'respect to the bulb surface or at least that portion thereof which is in contact with shoulder 58. If the filament is now secured to the bulb so that it occupies a redetermined position with respect to mem' or 56. it will also occupy a predetermined place in the lamp bulb.

To secure this result the glass stem 59 which supports the filament 60 in the usual .manner is inserted into a vertical central hole through another member 61 (see Fig. 2) mounted like member 56 to slide on standards 51. The filament is adjusted until it oc'cupies a predetermined position with respect to member61, this adjustment being made partly by bending the supporting wires 60 of the filament, and partly by sliding stem 59 up or down in member 61.

A set screw 59? m y be used to hold the 59 in this position. When the filament has .thus been brought into the desired position relative to member 61, this member is placed on top of member 56 as shown in Fig. 2, so that the filament is then supported at a definite position relative to the lamp bulb. The filament is secured to the lamp bulb when in this position by fusing together the neck ofthe bulb and the stem 59 and then removing the part of the stem extending beyond the neck of the bulb as is well understood by those versed in the art.

lVith the filament thus secured in a definite place in the bulb it is necessary only to fasten a lamp base at a definite position thereon to secure a definite location of the filament with respect to the lamp base. Accordingly, the members 61 and 56 are removed from standards 51 and replaced'by similar third member 62 (see Fig. 3) which has a central hole for receiving a lamp base B of any suitable type. The base here shown comprises a metallic shell 64 one end of which is flanged to form a surface similar to shoulder 58 on member- 56. This flange rests on the part of the surface of the lamp bulb previously occupied by shoulder 58 on member 56, and consequently the filament which has been fixed in a definite position with respect to this part of the bulb, as

hereinbefore described, is also in a definite and predetermined position with respect to the lamp base.

The base may be secured to the lamp bulb in a manner usual in the art. The. base shown in the drawing comprises a glass disk 65 having a central hole for receivmg a hollow metallic eyelet 66 through which one of the lead-in wires ofthe filament is drawn. The other filament wire is threaded through a small hole in the shell 64. The shell is partly filled with cement in a'plastic condition and then applied to the lamp bulb. It is then located thereon by means 0 member 62 and held in this position until the cement has set. Member 62 is then lifted off standards 51 and the lamp is withdrawn from the clamp. The lead-in wires are out 01f to the required length and soldered at theilr ends to eyelet 66 and shell 64 respec-. tive y.

Although I have herein shown and described only one form of apparatus embodyingmy invention and have explained only one method embodying my invention, it is understood that various chan es and modifications may be made therem within the scope of the appended claims without departing from the spirit and scope of my inment with said member and at a predetermined distance from the filament.

3. The method of assembling an incandes- I cent lamp which consists in clamping the lamp bulb in a stationary supporting member, securing the filament in alinement with the filament supporting member, securing said filament supportin member in a predetermined position with respect to said lamp supporting member, fusing said lamp.

bulb to said filament supporting member and securing the lamp base to said bulb at a predetermined position with respect to said lamp supporting member.

4. Apparatus for assembling incandescent electric lamps, comprising means for securing the filament at a definite position in the bulb, and means for s'ecurin the lamp base at a definite position on said ulb.

5. Apparatus for assembling incandescent electric lamps, comprising means for securing the filament in the bulb at a definite position relative to part of-the bulb surface, and.

means for securing the lamp base at adefinite position'relative to said part of the bulb surface. 7

6. In combination, means for holding a lamp bulb, means for adjusting said bulb into a definite position in said bulb holding means, said means comprising a member held in a definite position relative to a portion of the surface of said bulb, a member for temporarily supporting a lamp filament in a definite position, means for bringing said member into a definite position relative to said first-mentioned member when said filament is inserted into the bulb, means for securing the filament in the bulb in said position, means for adjusting the lamp base on said bulb with respect to the said portion of the bulb surface and means for securing the base to the bulb in said adjusted position.

7. The method of assembling the parts of an incandescent lamp so that they bear a definite relation to each other, which consists in clamping the lam bulb in a support, adjusting the lamp bulE into a definite position .on said support, securing the filament in a definite position relative to a temporary supporting member, bringing said filament supporting member into a definite position with respect to a portion of the surface of the bulb when said filament is inserted into said bulb, securing the filament in'said bulb, and

'sists in securing affixing a base to said bulb in a definite position relative to said portion of the bulb surface.

8. The method of assembling the parts of an incandescent lamp so that they bear a definite relation to each other,- which cona definite position with respect to part of the bulb surface, and fixing the lamp base the filament in the bulb at to the'bulb in a definite position relative to 10 the same portion of the surface of the bulb.

In testimony whereof I aflix my signature in presence of two witnesses.

CLINTON O. HARRINGTON.

Witnesses:

A. HERMAN Wnemm, C. W. DUNHAM. 

